Hi, there. I am a new PhD student and need to read a lot of papers. So I want to buy a tablet for the job. Typically, a paper is in A4 PDF. And I need tools like annotation (better with mathematical formula input). Someone recommends the new iPad for me because of the retina display. On the other hand, Kindle Paperwhite has come out, with E-ink suitable for reading. Also, there are tablets with 11.6" or even 13.3" display, which can better fit the size of A4. I am quite confused.

I'm a researcher and use my iPad3 extensively for work. iAnnotate, GoodReader and PDF Expert are all excellent annotation apps and they sync via dropbox. I used to have an iPad2 and while I'm not someone who typically upgrades every time a technological gadget comes in a new version, I exchanged it with a 3gen because of the retina display. When you are reading academic articles/pdfs for several hours a day, the screen resolution makes a difference. The screen size allows for comfortable pdf reading, IMO - I don't have to zoom in to read.

In addition, I also use Sente for bibliography management (this syncs with my mac), but you can also use Mendeley or Papers.

My recommendation is to definitely go for a tablet rather than an e-ink reader. I've outlined some of the reasons here, in other thread:

I'm a researcher and use my iPad3 extensively for work. iAnnotate, GoodReader and PDF Expert are all excellent annotation apps and they sync via dropbox. I used to have an iPad2 and while I'm not someone who typically upgrades every time a technological gadget comes in a new version, I exchanged it with a 3gen because of the retina display. When you are reading academic articles/pdfs for several hours a day, the screen resolution makes a difference. The screen size allows for comfortable pdf reading, IMO - I don't have to zoom in to read.

In addition, I also use Sente for bibliography management (this syncs with my mac), but you can also use Mendeley or Papers.

My recommendation is to definitely go for a tablet rather than an e-ink reader. I've outlined some of the reasons here, in other thread:

Thank you for your answer with great detail! Since Nexus 10 is coming out, will you recommend this tablet?

I don't know much about it, but I'm sure it will do the job in terms of supporting pdf reading and annotation. I don't know how what dedicated android apps are out there for pdf management, but they probably exist. In any case, a folder structure in DropBox combined with iAnnotate for android would get you very far.

Seems like the nexus actually beats the iPad for screen specs, at least for ppi, so that's something to consider for reading purposes. On the other hand, the iPad will give you more max storage with 64GB vs max 32GB on the Nexus. 32GB will get you very very far, though, if you're planning to primarily store pdf documents (as opposed to music and videos).

Another consideration is the operating system. If you have a mac or an iPhone, you might want consistency and go for the iPad; if you have an android phone, that could make you lean towards the Nexus.

Seems like the Nexus doesn't have a 3/4G version yet, which would be a deal breaker for me, but it comes down to use patterns - a lot of people with iPads have wifi only and don't feel the need for 3g.

you might also consider the Samsung Galaxy Note 10.1. The screen resolution isn't as good as the iPad's, but you have a WACOM digitizer with a pen that works like a real pen for drawings, handwritten notes, etc.

You can also display two programs on the screen, something no Apple device nor any other Android device can do. It helps a lot when making comparison or looking things up on the web, etc.

I don't know much about it, but I'm sure it will do the job in terms of supporting pdf reading and annotation. I don't know how what dedicated android apps are out there for pdf management, but they probably exist. In any case, a folder structure in DropBox combined with iAnnotate for android would get you very far.

Seems like the nexus actually beats the iPad for screen specs, at least for ppi, so that's something to consider for reading purposes. On the other hand, the iPad will give you more max storage with 64GB vs max 32GB on the Nexus. 32GB will get you very very far, though, if you're planning to primarily store pdf documents (as opposed to music and videos).

Another consideration is the operating system. If you have a mac or an iPhone, you might want consistency and go for the iPad; if you have an android phone, that could make you lean towards the Nexus.

Seems like the Nexus doesn't have a 3/4G version yet, which would be a deal breaker for me, but it comes down to use patterns - a lot of people with iPads have wifi only and don't feel the need for 3g.

Thanks very much again for your kindness! Actually I want to buy a Nexus 4 too so Nexus 10 may be my first choice.

Also, I usually stay in the campus so I think there will be quite a few hotspots.

you might also consider the Samsung Galaxy Note 10.1. The screen resolution isn't as good as the iPad's, but you have a WACOM digitizer with a pen that works like a real pen for drawings, handwritten notes, etc.

You can also display two programs on the screen, something no Apple device nor any other Android device can do. It helps a lot when making comparison or looking things up on the web, etc.

Why does Galaxy Note have this feature? I mean, it is running Android too... are there some hotkeys on the device?